#!/bin/sh
#
# Add a Google Analytics tag to static website files
# @see http://adambuchanan.me/post/26345221717/updating-google-analytics-code-on-many-static-pages
# Tested on MacOS 10.8.X
#
# Usage:
#   Set the GA parameters below
#   Execute the script from the top-level of the static site
#

GA_TRACKER_ID='UA-XXXXXXX-X'
GA_DOMAIN='YOUR-DOMAIN.COM'

GA_CODE=$(cat <<EOF
<!-- Start Google Analytics Installation -->
<script>
  (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
  (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
  m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
  })(window,document,'script','\/\/www.google-analytics.com\/analytics.js','ga');

  ga('create', '${GA_TRACKER_ID}', '${GA_DOMAIN}');
  ga('send', 'pageview');

<\/script>
<!-- End Google Analytics Installation -->
EOF)

# remove newlines
GA_CODE=`echo ${GA_CODE} | sed -e 's/\n//g'`

#echo ${GA_CODE}
#exit


# set placeholder text before the </head> tag for the code to be replaced with later.
for match in `grep -n -r "</head>" . | grep -v .sh`; do
    file=`echo $match | cut -d":" -f1`
    line=`echo $match | cut -d":" -f2`
    sed -e "`echo $line`s/<\/head>/GOOGLE_ANALYTICS_CODE_HERE<\/head>/" -i '' "$file"
done


# insert the tracker code
for match in `grep -n -r "GOOGLE_ANALYTICS_CODE_HERE" . | grep -v .sh`; do
    file=`echo $match | cut -d":" -f1`
    sed -e "s/GOOGLE_ANALYTICS_CODE_HERE/${GA_CODE}/" -i '' "$file" 
done